Here's the definition that's on our security deposit page, which doesn't get into the nitty-gritty: Normal wear and tear is a term that Wisconsin law does not define.
(3)Protein Fat-Free Percentage, Protein Fat-Free Content, PFF Percentage, PFF Content or PFF of a product means the meat protein (indigenous to the raw, unprocessed pork cut) content expressed as a percent of the non-fat portion of the finished product.
The new regulation is based on an evaluation of the meat protein (after the fat has been removed) in the finished product. The old regulations were concerned with the amount of curing solution (basically water) left in the ham after curing. When we buy meat, we are paying for meat protein, not water. This new regulation will give consumers much better assurance that they are getting what they pay for. To better understand the new PFF regulations, a little ham history might help.